title: Naturally occurring IgG anti-HLA alloantibody does not correlate with HIV type 1 resistance in Nairobi prostitutes.
abstract: In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
authors.affiliation: Department of Immunology, University of Toronto, The Toronto Hospital, Canada.
authors.forename: M A
authors.initials: MA
authors.lastname: Luscher
authors.forename: G
authors.initials: G
authors.lastname: Choy
authors.forename: E
authors.initials: E
authors.lastname: Njagi
authors.forename: J J
authors.initials: JJ
authors.lastname: Bwayo
authors.forename: A O
authors.initials: AO
authors.lastname: Anzala
authors.forename: J O
authors.initials: JO
authors.lastname: Ndinya-Achola
authors.forename: T B
authors.initials: TB
authors.lastname: Ball
authors.forename: J A
authors.initials: JA
authors.lastname: Wade
authors.forename: F A
authors.initials: FA
authors.lastname: Plummer
authors.forename: B H
authors.initials: BH
authors.lastname: Barber
authors.forename: K S
authors.initials: KS
authors.lastname: MacDonald
mesh_terms: D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D006801:Humans; D007113:Immunity, Innate; D007074:Immunoglobulin G / Q000276:immunology*; D007518:Isoantibodies / Q000097:blood*; D007630:Kenya; D008137:Longitudinal Studies; D011477:Sex Work
chemical_list: D015395:Histocompatibility Antigens Class I; D007074:Immunoglobulin G; D007518:Isoantibodies